A smart card resembles a credit card in size and shape. (See ISO 7810). The inside of a smart card usually contains an embedded 8-bit microprocessor. The microprocessor is under a gold contact pad on one side of the card. Smarts cards may typically have 1 kilobyte of RAM, 24 kilobytes of ROM, 16 kilobytes of programmable ROM, and an 8-bit microprocessor running at 5 MHz. The smart card uses a serial interface and receives its power from external sources like a card reader. The processor uses a limited instruction set for applications such as cryptography. The most common smart card applications are:                Credit cards        Electronic cash        Computer security systems        Wireless communication        Loyalty systems (like frequent flyer points)        Banking        Satellite TV        Government identification        
Smart cards can be used with a smart-card reader attachment to a personal computer to authenticate a user. (However, these readers are relatively costly, and have not been well accepted by users.) Web browsers also can use smart card technology to supplement Secure Sockets Layer (SSL) for improved security of Internet transactions. The American Express Online Wallet shows how online purchases work using a smart card and a PC equipped with a smart-card reader. Smart-card readers can also be found in vending machines.
There are three basic types of smart cards: contact chip, contactless and dual interface (DI) cards.
A contact smart card (or contact chip card) is a plastic card about the size of a credit card that has an embedded integrated circuit (IC) chip to store data. This data is associated with either value or information or both and is stored and processed within the card's chip, either a memory or microprocessor device.
The predominant contact smart cards in consumer use are telephone cards as a stored value tool for pay phones and bank cards for electronic cash payments. Contact smart cards require the placement of the card in a terminal or automatic teller machine for authentication and data transaction. By inserting the contact smart card into the terminal, mechanical and electrical contact is made with the embedded chip module.
Contactless smart cards have an embedded antenna connected to a microchip, enabling the card to pick up and respond to radio waves. The energy required for the smart card to manipulate and transmit data is derived from the electromagnetic field generated by a reader. Contactless smart cards do not require direct contact with the reader because they employ the passive transponder technology of Radio Frequency Identification (RFID). By just waving the card near the reader, secure identification, electronic payment transaction and authentication are completed in milliseconds.
Contactless chip card technology is based on two standards: ISO/IEC 14443 Type A and Type B (for proximity cards), and ISO/IEC 15693 (for vicinity cards). Cards that comply with these standards operate at the 13.56 MHz frequency. ISO/IEC 14443 products have a range of up to 10 cm (centimeters), while ISO/IEC 15693 products can operate at a range between 50 and 70 cm.
Dual interface (DI) cards, sometimes called combination chip cards, are microprocessor multi-function cards that incorporate both the functions of a contact chip card and a contactless card. Within the smart card is a microprocessor or micro-controller chip with radio frequency identification (RFID) capability that manages the memory allocation and file access. The on-board memory is shared and can be accessed either in contact or contactless mode.
This type of chip is similar to those found inside all personal computers and when implanted in a smart card, manages data in organized file structures, via a card operating system. This capability permits different and multiple functions and/or different applications to reside on the card.
A dual interface (DI) card is ideal for single and multi-application markets ranging from micro-payment (convenient alternative to low value cash transaction) to e-commerce and from ticketing in mass transit to secure identification for cross border control. Originally, such cards were intended to be used in conjunction with a reader connected to a PC for downloading tickets, tokens, or electronic money via the contact interface and used in contactless mode in the application for physical access or proximity payment
Passive radio frequency identification (RFID) devices derive their energy from the electromagnetic field radiated from the reader. Because of international power transmission restrictions at the frequencies of 125 KHz and 13.56 MHz, the contactless integrated circuits are generally low voltage and low power devices. Read/Write circuits use low voltage EEPROM and low power analogue cells. The read/write memory capacity in transponders, contact smart cards, contactless memory based smart cards, dual interface smart cards (contact & contactless) and multi-interface micro-controllers is generally limited to approximately 64 kilobytes.
Contactless Interfaces
As used herein, “contactless interfaces” refers to high radio frequency (RF) connections between one device and another, typically over a very short distance, such as only up to 50 cm. The following are examples of contactless interfaces and/or devices that typically connect via a contactless interface.    ISO 14443 ISO 14443 RFID cards; contactless proximity cards operating at 13.56 MHz with a read/write range of up to 10 cm. ISO 14443 defines the contactless interface smart card technical specification.    ISO 15693 ISO standard for contactless integrated circuits, such as used in RF-ID tags. ISO 15693 RFID cards; contactless vicinity cards operating at 13.56 MHz with a read/write range of up to 100 cm. (ISO 15693 is typically not used for financial transactions because of its relatively long range as compared with ISO 14443.)    NFC Short for “Near Field Communication”. NFC is a contactless connectivity technology that enables short-range communication between electronic devices. If two devices are held close together (for example, a mobile phone and a personal digital assistant), NFC interfaces establish a peer-to-peer protocol, and information such as phone book details can be passed freely between them. NFC devices can be linked to contactless smart cards, and can operate like a contactless smart card, even when powered down. This means that a mobile phone can operate like a transportation card, and enable fare payment and access to the subway. NFC is an open platform technology standardized in ECMA (European Computer Manufacturers Association) 340 as well as ETSI (European Telecommunications Standards Institute) TS 102 190 V1.1.1 and ISO/IEC 18092. These standards specify the modulation schemes, coding, transfer speeds, and frame format of the RF interface of NFC devices, as well as initialization schemes and conditions required for data collision-control during initialization—for both passive and active modes.    RFID Short for “Radio Frequency Identification”. An RFID device interacts, typically at a limited distance, with a “reader”, and may be either “passive” (powered by the reader) or “active” (having its own power source, such as a battery).Wireless Versus Contactless Interfaces
Wireless and Contactless are two types of radio frequency (RF) interfaces. In a most general sense, both are “wireless” in that they do not require wires, and that they use RF. However, in the art to which this invention most nearly pertains, the terms “wireless” and “contactless” have two very different meanings and two very different functionalities.
Wireless interfaces are exemplified by WLAN, Zigbee, Bluetooth and UWB. These wireless interfaces operate at a distance of several meters, generally for avoiding “cable spaghetti” for example, Bluetooth for headsets and other computer peripherals. WLAN is typically used for networking several computers in an office.
The contactless interfaces of interest in the present invention are principally RFID contactless interfaces such as ISO 14443, 15693 and NFC. RFID operates at a maximum distance of 100 cm for the purpose of identification in applications such as access control. In a payment (financial transaction) application, the distance is restricted to 10 cm. For example, a contactless RFID smart card protocol according to ISO 14443 can be used for private, secure financial transactions in “real world” applications such as payment at a retailer.
Wireless and contactless use different communications protocols with different capabilities and are typically used for very different purposes. Note, for example, that 100 cm (ISO 15693, an RFID contactless protocol) is considered to be too great a distance to provide appropriate security for (contactless) financial transactions. But 100 cm would not be enough to provide a (wireless) network between office computers! Additionally, generally, contactless technology is primarily passive (having no power source of its own), deriving power to operate from the electromagnetic field generated by a nearby reader. Also, contactless technology, using the smart card protocol, is used for secure identification, authentication and payment. Wireless technologies, on the other hand, generally require their own power source (either batteries, or plugged in) to operate. Contactless is different than wireless; different protocol, different signal characteristics, different utility, different energy requirements, different capabilities, different purposes, different advantages, different limitations.
Secure Inlays
As used herein, an “inlay”, particularly a “secure inlay” comprises an inlay site containing a high frequency RFID chip and an antenna embedded into a multi-layer substrate and connected to the terminals (terminal areas) of the RFID chip.
Typically, in the manufacture of a secure inlay, the RFID chip is positioned in a recess in a layer of the substrate, supported by a lower substrate layer, then a wire conductor is embedded or countersunk onto or into the top substrate layer in the direction of the RFID chip. Then, the wire conductor is guided over a first terminal area of the RFID chip, then the embedding process is continued by forming an antenna in the top substrate layer with a given number of turns. Then the wire is guided over the second terminal area. And, finally, the wire conductor is again embedded into the top substrate layer before cutting the wire to complete the high frequency transponder site.
In a next stage of the production process, the wire ends passing over the terminal areas are interconnected by means of thermal compression bonding. Adhesively placing a wire conductor onto the top substrate layer is an alternative to embedding, and typically involves self-bonding coated wire conductor.
A wire embedding apparatus may be an ultrasonic wire guide tool, known as a “sonotrode”, with a wire feed channel (capillary) passing through the center of the wire guide tool. The wire conductor is fed through the wire guide tool, emerges from the tip, and by application of pressure and ultrasonic energy the wire conductor is “rubbed” into the substrate, resulting in localized heating of the wire conductor and subsequent sinking of the wire conductor into the substrate material during the movement of the wire guide tool. A wire placement apparatus may also be an ultrasonic tool similar in function to an ultrasonic horn which heats the wire to form an adhesion with a substrate.
U.S. Pat. No. 6,698,089 (“089 patent”), incorporated by reference in its entirety herein, discloses device for bonding a wire conductor. Device for the contacting of a wire conductor in the course of the manufacture of a transponder unit arranged on a substrate and comprising a wire coil and a chip unit, wherein in a first phase the wire conductor is guided away via the terminal area or a region accepting the terminal area and is fixed on the substrate relative to the terminal area or the region assigned to the terminal area by a wire guide and a portal, and in a second phase the connection of the wire conductor to the terminal area is effected by means of a connecting instrument. FIGS. 1 and 2 of the 089 patent show a wire conductor 20 being embedded in a surface of a substrate 21, by the action of ultrasound. FIG. 3 of the 089 patent shows a wiring device 22 with an ultrasonic generator 34, suitable for embedding the wire. It is believed that the wiring device in the 089 patent can also be used for adhesively placing a wire.
U.S. Pat. No. 5,281,855, incorporated by reference in its entirety herein, discloses a method and apparatus for facilitating interconnection of lead wires to an integrated circuit including the provision of an additional protective layer of insulation to the top of an integrated circuit chip or die and the provision of enlarged plated electrodes to the surface of the additional insulation to form enhanced bonding pads, such pads being electrically connected through the protective layers to the normal bonding pads of the integrated circuit device. The enhanced bonding pads are made of a soft conductive metal such that external wires to be attached thereto can be bonded to the pads using a thermal compression bonding technique.
U.S. Pat. No. 6,088,230, incorporated by reference in its entirety herein, discloses a procedure for producing a transponder unit (55) provided with at least one chip (16) and one coil (18), and in particular a chip card/chip-mounting board (17) wherein the chip and the coil are mounted on one common substrate (15) and the coil is formed by installing a coil wire (21) and connecting the coil-wire ends (19, 23) to the contact surfaces (20, 24) of the chip on the substrate.
Canada Patent Application CA 2555034, incorporated by reference in its entirety herein, discloses a method for the production of a book-type security document with at least one security cambric (15) and at least one transponder unit (21), characterized in that: at least one laminated layer (22, 23) is applied at least on one side of the at least one security cambric (4 5) and on at least one side of the at least one transponder unit (21); the at least one security cambric (15) and the at least one transponder unit (21) are fully encompassed by the laminated layers (22, 23) and that a circumferential, closed edge (24) is provided by the laminated layers (22, 231, and that a laminated layer sheath (25) is formed.
U.S. Pat. No. 7,229,022, incorporated by reference in its entirety herein, discloses method for producing a contactless chip card and chip card. A method for producing a transponder, especially a contactless chip card (1) comprises at least one electronic component (chip module 2) and at least one antenna (3); the at least one electronic chip component (2) being disposed on a non-conducting substrate that serves as a support for the component. The at least one antenna is also disposed on a non-conducting substrate, the at least one electronic component (2) being applied to a first substrate and the antenna (3) on a second substrate. The entire circuit (1) is then produced by joining the individual substrates so that they are correctly positioned relative to each other. The components (2, 3) are contacted once the different substrates have been joined by means of auxiliary materials such as solder or glue, or without auxiliary materials by microwelding. The non-conducting substrates form a base card body.
PCT/US99/28795 (WO 00/36891), incorporated by reference in its entirety herein, discloses methods for wire-scribing filament circuit patterns with planar and non-planar portions. An apparatus and method of forming filament circuit patterns with planar and non-planar portions and interconnection cards, smart cards or optical fiber circuit cards formed therefrom are provided. A filament circuit path is scribed by moving a filament guide and a substrate relative to one another, and dispensing a filament on, or in the vicinity of, a surface of the substrate. The filament or the substrate or both have adhesive surface(s). The adhesive surface is capable of being adhesively actuated by application of energy. Energy is applied simultaneous with, or subsequent to, scribing. A portion of the filament circuit pattern is planar and another portion is non-planar. The non-planar portion traverses but does not contact or adhere to a pre-selected area of the substrate. The pre-selected area corresponds with a pad, a contact pattern, a hole, a slot, a raised feature, a part of the previously scribed planar portion of the pattern, and a filament termination point. Alternately, the non-planar portion may be embedded below the surface of the substrate. Another planar portion of the filament circuit traverses the non-planar portion but does not contact or adhere to a pre-selected part of the previously scribed non-planar portion. According to the above method wire-scribed circuit boards are formed including interconnection cards, smart cards or optical fiber circuit cards.
An Inlay and Transponder of the Prior Art
FIGS. 1A and 1B illustrate an inlay substrate (or sheet) 100 having a plurality of transponder areas. A selected one of the transponder areas 102 constituting a single transponder is shown in detail. The vertical and horizontal dashed lines (in FIG. 1A) are intended to indicate that there may be additional transponder areas (and corresponding additional transponders) disposed to the left and right of, as well as above and below, the transponder area 102, on the inlay sheet 100. Such a plurality of transponders may be arranged in an array on the (larger) inlay sheet. As best viewed in FIG. 1B, the inlay sheet 100 may be a multi-layer substrate 104 comprising one or more upper (top) layers 104a and one or more lower (bottom) layers 104b. (Each layer may be considered to be a substrate.)
A recess 106 may be formed in (through) the upper layer 104a, at a “transponder chip site”, so that a transponder chip 108 may be disposed in the recess, and supported by the lower layer 104b. The transponder chip 108 is shown having two terminals 108a and 108b on a top surface thereof. The transponder chip 108 may be a chip module, or an RFID chip.
Generally, the recess 106 is sized and shaped to accurately position the transponder chip 108, having side dimensions only slightly larger than the transponder chip 108 to allow the transponder chip 108 to be located within the recess. For example,                1. the transponder chip 108 may measure: 5.0×8.0 mm        2. the recess 106 may measure: 5.1×8.1 mm        3. the terminals 108a/b may measure: 5.0×1.45 mm        4. the wire (discussed below) may have a diameter between 60 and 112 μm        
One millimeter (mm) equals one thousand (1000) micrometers (μm, “micron”).
In FIGS. 1A and 1B, the recess 106 may be illustrated with an exaggerated gap between its inside edges and the outside edges of the chip 108, for illustrative clarity. In reality, the gap may be only approximately 50 μm-100 μm (0.05 mm-0.1 mm).
In FIG. 1A the terminals 108a and 108b are shown reduced in size (narrower in width), for illustrative clarity. (From the dimensions given above, it is apparent that the terminals 108a and 108b can extend substantially the full width of the transponder chip 108.)
It should be understood that the transponder chip 108 is generally snugly received within the recess 106, with dimensions suitable that the chip 108 does not move around after being located within the recess 106, in anticipation of the wire ends 110a, 110b being bonded to the terminals 108a, 108b. As noted from the exemplary dimensions set forth above, only very minor movement of the chip 108, such as a small fraction of a millimeter (such as 50 μm-100 μm) can be tolerated.
As best viewed in FIG. 1A, an antenna wire 110 is disposed on a top surface (side) of the substrate, and may be formed into a flat (generally planar) coil, having two end portions 110a and 110b. 
The substrate 100 may be in the form of a credit card, having a width (horizontal, as illustrated) of approximately 48 mm, and a length (vertical, as illustrated in FIG. 1A) of approximately 80 mm.
The antenna 110 may be formed by 4 or 5 turns of wire, such as coated wire, having a diameter of 0.08 mm (80 μm), and located just inside of (for example, 3-5 mm in from the edge of) the periphery of the substrate. Hence, each turn of wire may extend approximately 45 mm×75 mm×45 mm×75 mm (minus the dimension of the chip 108), or about 240 mm, so 4 turns would have a total length of approximately 1 meter. The pitch, or spacing between turns of wire may be about 0.46 mm. The resonant frequency of the antenna, connected with the chip, may be 13.56 MHz, conforming to ISO 14443.
As best viewed in FIG. 1B, the antenna wire is “mounted” to the substrate, which includes “embedding” (countersinking) the antenna wire into the surface of the substrate, or “adhesively placing” (adhesively sticking) the antenna wire on the surface of the substrate. In either case (embedding or adhesively placing), the wire typically feeds out of a capillary 116 of an ultrasonic wire guide tool (not shown). The capillary 116 is typically disposed perpendicular to the surface of the substrate 100. The capillary 116 is omitted from the view in FIG. 1A, for illustrative clarity.
The antenna wire 110 may be considered “heavy” wire (such as 60 μm-112 μm), which requires higher bonding loads than those used for “fine” wire (such as 30 μm). Rectangular section copper ribbon (such as 60×30 μm) can be used in place of round wire.
The capillary 116 may be vibrated by an ultrasonic vibration mechanism (not shown), so that it vibrates in the vertical or longitudinal (z) direction, such as for embedding the wire in the surface of the substrate, or in a horizontal or transverse (y) direction, such as for adhesively placing the wire on the surface of the substrate. In FIG. 1B, the wire 110 is shown slightly spaced (in drawing terminology, “exploded” away) from the substrate, rather than having been embedded (countersunk) in or adhesively placed (stuck to) on the surface of the substrate.
The antenna wire 110 may be mounted in the form of a flat coil, having two ends portions 110a and 110b. The ends portions 110a and 110b of the antenna coil wire 110 are shown extending over (FIG. 1A) and may subsequently be connected, such as by thermal-compression bonding (not shown), to the terminals 108a and 108b of the transponder chip 108, respectively.
Examples of embedding a wire in a substrate, in the form of a flat coil, and a tool for performing the embedding (and a discussion of bonding), may be found in the aforementioned U.S. Pat. No. 6,698,089 (refer, for example, to FIGS. 1, 2, 4, 5, 12 and 13 of the patent). It is known that a coated, self-bonding wire will stick to a synthetic (e.g., plastic) substrate because when vibrated sufficiently to soften (make sticky) the coating and the substrate.
In FIG. 1B, the wire 110 is shown slightly spaced (in drawing terminology, “exploded” away) from the terminals 108a/b of the transponder chip 108, rather than having been bonded thereto, for illustrative clarity. In practice, this is generally the situation—namely, the end portions of the wires span (or bridge), the recess slightly above the terminals to which they will be bonded, in a subsequent step. Also illustrated in FIG. 1B is a “generic” bond head, poised to move down (see arrow) onto the wire 110b to bond it to the terminal 108b. The bond head 118 is omitted from the view in FIG. 1A, for illustrative clarity.
The interconnection process can be inner lead bonding (diamond tool), thermal compression bonding (thermode), ultrasonic bonding, laser bonding, soldering, ColdHeat soldering (Athalite) or conductive gluing.
As best viewed in FIG. 1A, in case the antenna wire 110 needs to cross over itself, such as is illustrated in the dashed-line circled area “c” of the antenna coil, it is evident that the wire should typically be an insulated wire, generally comprising a metallic core and an insulation (typically a polymer) coating. Generally, it is the polymer coating that facilitates the wire to be “adhesively placed” on (stuck to) a plastic substrate layer. (It is not always the case that the wire needs to cross over itself. See, for example, FIG. 4 of U.S. Pat. No. 6,698,089).
In order to feed the wire conductor back and forth through the ultrasonic wire guide tool, a wire tension/push mechanism (not shown) can be used or by application of compressed air it is possible to regulate the forward and backward movement of the wire conductor by switching the air flow on and off which produces a condition similar to the Venturi effect.
By way of example, the wire conductor can be self-bonding copper wire or partially coated self bonding copper wire, enamel copper wire or partially coated enamel wire, silver coated copper wire, un-insulated wire, aluminum wire, doped copper wire or litz wire.
FIG. 1A herein resembles FIG. 5 of U.S. Pat. No. 6,698,089 (the '089 patent), which has a similar coil antenna (50) with an initial coil region (51) and a final coil region (52) comparable to the antenna 110 with two end portions 110a and 110b described herein. In the '089 patent, the coil (50) is arranged on a substrate 55 which comprises a substrate recess (56, compare 106 herein) in the interior region (53) of the coil (50).
In FIG. 5 of the '089 patent, it can be seen that the initial and final coil regions (end portions) of the wires extend across the recess. In FIG. 6 of the '089 patent, it can be seen that the recess extends completely through the substrate. If the antenna is mounted to the substrate prior to the chip being installed in the recess (and the antenna is mounted to the front/top surface/side of the substrate, as shown), due to the fact that the antenna wires are “blocking” entry to the recess from the top/front surface of the substrate, the chip must be installed into the recess from the back (bottom) side of the substrate, as indicated by FIG. 6 of the '089 patent.
FIG. 7 of the '089 patent shows the subsequent (inter)connection of the terminal areas 59 of the chip unit 58 to the initial coil region 51 and to the final coil region 52 by means of a thermode 60 which under the influence of pressure and temperature creates a connection by material closure between the wire conductor 20 and the terminal areas 59, as an overall result of which a card module 64 is formed.
Contactless Cards with Switches
US Patent Publication No. 2007/0290051, incorporated by reference in its entirety herein, discloses contactless card with membrane switch made of elasto-resistive material. The card (1), such as a credit card or other similar card, comprises at least a RFID chip module (3) and an antenna (4). The antenna (4) is interrupted in an interruption zone with two separated contact ends (5′,5″) and a contacting material (10) is placed in said interruption zone in order to enable a contact between said two separated ends (5′,5″). Said contacting material (10) becomes conductive under pressure so that the antenna is functional only when the contacting material (10) is put under pressure by a user. As disclosed therein:                A switch is mounted on contactless cards, in particular credit cards, for improving security of said card and reducing the risk of forgery.        Contactless cards with a switch are known in the art. Such chip cards usually incorporates one or several switches which can be manually operated and allow the electronics or parts of the electronics of the card to be manually switched on or off so as to release data and characteristics of the chip card only in accordance with the choice of the user of the chip card. This renders the unauthorized identification of the chip card more difficult. The activation of such a card by switches in the plastic card is also possible in emergency situations.        A typical example is disclosed in DE 197 42 126 which relates to a portable data medium with an activation switch. In this prior art, a switching device operated by the user is connected between the antenna and the chip so that reception of data is only possible after activation of the switching device. Further examples are given by DE 19542 900, U.S. Pat. No. 5,376,778 and U.S. Pat. No. 4,897,644.        PCT publication WO 98/20450 discloses an identification card with a transaction coil and a method for manufacturing such card. The transaction coil is formed from a silver or generally conductive paste silk screen component which is incorporated in a plastic card body corresponding to the conventional ISO standards and whose ends are subsequently bared by means of a milling process for implanting a special chip module, or whose contact ends have already been kept free in a lamination or injection-molding process, and whose contacting can only be realized by intentionally exerting pressure and becomes automatically inactive after ending this pressure. The deliberate switching of a transponder coil is essential in this case. However, this card is also very elaborate as regards its manufacture and, in operation, it is sensitive to disturbances.        More recently, for example in WO 05/062245, the idea is to provide an antenna switch which allows, in a switched on position, the electrical contacting of two antenna pads such that the contactless communication with a reader is enabled. In a switched-off position, the pads of the antenna are electrically disconnected and the contactless communication with the reader is disabled.        Other similar devices are known from US 2003/132301, DE 10140662, U.S. Pat. No. 5,696,363 and U.S. Pat. No. 6,343,744, all of which are, incorporated by reference in their entirety herein.        All the examples cited above propose a mechanical switch, however, rather complicated from a manufacturing point of view and, in operation, it is sensitive to disturbances.        Other examples of an electronic card with a function which can be manually activated but avoiding the use of a mechanical switch are known from U.S. Pat. No. 6,424,029 and FR 2 728 710, both of which are, incorporated by reference in their entirety herein.        In U.S. Pat. No. 6,424,029, incorporated by reference in its entirety herein, a chip card is described, preferably a contactless chip card, comprising a data-processing circuit for receiving, processing and/or transmitting data signals, and at least a capacitive switching element which can be activated by means of a user's touch. The activation of the switching element triggers at least the transmission of data signals from the data-processing circuit and without whose activation at least the transmission of data signals from the data-processing circuit is prevented.        In FR 2 728 710, incorporated by reference in its entirety herein, the electronic card has a plastic body comprising the function components that are fed from the battery. The battery is connected to a sensor whose physical properties vary due to its manual operation. An electronic circuit monitors the operation of the function components independently of the state of the sensor. A resistance strain gauge may be used as a sensor which reacts to bending of the card, or a thermistor may be used which responds to the warmth of a user's finger touching the card. The sensor may also comprise pairs of electrodes between which the resistance changes upon a user's touch. For a reliable operation, the components should only be activated when the rate of change of the physical property detected by the sensor is within a predetermined range.        These sensors have proved to be unreliable. For example, the responses of a thermistor or a thermoelement or the resistor between two electrodes may be dependent on the temperature of the user's finger or on the fact whether the user wears gloves.Related Patent References        
U.S. Pat. No. 5,084,699, incorporated by reference in its entirety herein, describes an impedance matching coil assembly for an inductively coupled transponder. A coil assembly for use in an inductively powered transponder including a primary coil and a secondary coil wrapped around the same coil forming ferrite rod. The primary coil's leads are left floating while the secondary coil's leads are connected to the integrated identification circuit of the transponder. There are approximately three times as many turns to the primary coil as there are turns to the secondary coil. The primary coil is configured to self resonate at the operating frequency of the identification circuit when brought within range of an interrogator's magnetic field, thereby creating a voltage across the primary coil having a high source impedance. The secondary coil is configured to resonate at the same operating frequency, but to convert the high source impedance level of the primary coil to a low source impedance level, which is more suitable for powering the identification circuit and which substantially matches the impedance level of the secondary coil to the impedance level of the interrogator field, thereby maximizing the quantity of energy which can be transferred between the interrogator and the transponder.
Canadian patent application CA 2,279,176, incorporated by reference in its entirety herein, describes a transmission module for a transponder device, transponder device and method for operating said device. The invention relates to a transmission module (14) for contactless transmission of data between a chip (15) and a reading device (12) with a coil arrangement comprising a coupling element (19 and at least one antenna coil (20) that are electrically interconnected, wherein said coupling element is used to produce inductive coupling with a transponder coil (18) which is electrically connected to the chip, and the antenna coil is used to enable connection to the reading device. The coupling element embodied as a coupling coil (19) and the antenna coil (20) are configured differently with respect to the coil parameters affecting coil impedance.
U.S. Pat. No. 6,111,288, incorporated by reference in its entirety herein, describes a new switching element and a circuit device and the like using the same element are provided, which comprises semiconductor in which a channel region is formed at an interface with an insulating film, first and second terminals S, D, which are located in corresponding manner to both ends of the channel region, and through which a tunnel current is let to flow into the channel region, and a third terminal G giving a high frequency vibration to a potential barrier of the channel region through the insulating film, wherein the tunnel current flowing into the channel region is increased as a value of an exponential function is increased with a predetermined threshold vibration frequency as a boundary value.
U.S. Pat. No. 6,522,308, incorporated by reference in its entirety herein, disclosed variable capacitance coupling antenna and concerns a coupling antenna connected to an electromagnetic wave transceiver device containing one or several integrated capacitors. This coupling antenna includes at least one screen printed turn (24) on a support (28) consisting of an insulating dielectric support and also includes a screen printed capacitor on the support, connected in parallel, thereby reducing the capacitance supplied by the capacitor(s) built into the device, so that the resulting capacitance forms a resonating circuit with the turn. The invention also concerns the fabrication process of such an antenna and the use of this antenna in a contactless or hybrid contact-contactless smart card.
U.S. Pat. No. 7,093,499, incorporated by reference in its entirety herein, describes a force sensor, or a method, determines a force using at least a measured inductance in a coil wherein a quantum tunneling composite is located in a magnetic path created by the coil, is positioned in a load path of the force, and is under strain from the force. A strain sensor, or a method, determines a strain using at least a measured inductance in a coil wherein a quantum tunneling composite is located in a magnetic path created by the coil, is positioned in a load path of a force, and is under strain from the force.
U.S. Pat. No. 7,145,432 and US Patent Application 20060255903, incorporated by reference in their entirety herein, describe a flexible switching device in which an electronic resistor user interface comprises flexible conductive materials and a flexible variably resistive element capable of exhibiting a change in electrical resistance on mechanical deformation and is characterized by textile-form electrodes (10, 12) a textile form variably resistive element (14) and textile-form members (16) connective to external circuitry.
U.S. Pat. No. 5,034,648, incorporated by reference in its entirety herein, describes a piezo film switch which comprises a cantilever with a pair of layers, including a piezo film layer and a flexible, backing layer laminated thereto. The piezo film layer produces a positive or negative output pulse, depending upon a direction of deflection of the cantilever. Interface circuitry coupled to the piezo film layer is powered by the output pulses and provides “pseudo contact closures” which emulate the operation of a mechanical switch.
U.S. Patent Application 2007/0290051 describes a contactless card with membrane switch made of elasto-resistive material whereby the card such as a credit card or other similar card, comprises at least a RFID chip module and an antenna. The antenna is interrupted in an interruption zone with two separated contact ends and a contacting material is placed in said interruption zone in order to enable a contact between said two separated ends. Said contacting material becomes conductive under pressure so that the antenna is functional only when the contacting material is put under pressure by a user.
Patent References Related To Displays
U.S. Pat. No. 6,879,424 describes an electrochromic display device and compositions useful in making such devices. It relates to a composition and to a display device having the composition positioned between electrodes. The composition contains: (a) a compound that undergoes a reversible redox reaction to generate a pH gradient between the two electrodes, (b) an indicator dye, (c) a charge transport material, and optionally, (d) a matrix material and (e) an opacifier, and (f) secondary redox couple wherein components (a), (b), and (c) are different from one another and the standard reduction potential of component (a) is less than the standard reduction potential for the other components. Depending on the electric field present between the electrodes, a display image may be generated.
U.S. Pat. No. 7,054,050, incorporated by reference in its entirety herein, describes an electrochromic display device which is a display device comprising a solid top transparent, charge conducting material, positioned below the transparent solid material is an active layer comprising an electrochromic material and an electrolyte, and positioned below the active layer is a working electrode and a counter-electrode arranged to be isolated from one another, wherein the distance between the working and the counter electrode is greater than two times the thickness of the active layer between the electrode and the conductive material.
U.S. Pat. No. 4,014,602, incorporated by reference in its entirety herein, describes an identification card having a hologram superimposed on printed data. A falsification-proof identity card comprises a first transparent layer on the underneath side of which conventional data is applied by printing technology. The card contains a holographic safeguard and additional safety measures such as metal structures, fluorescent structures, safety imprints and the like which are only visible in response to holographic reconstruction and/or other light applications, such as ultra-violet light. The holographic safeguard comprises a second transparent or non-transparent layer which carries on the entire surface which faces the first layer a phase hologram or an amplitude hologram which can be read out by light transmission or by light reflection, depending on the transparency of the layer, and which contains at least the visible data printed on the first layer in a direct recording.